The impact of farmer field schools in productivity, efficiency and environmental sustainability of facility vegetable production

China produces half of the world’s vegetables on only 1.7% of global croplands, yet accounts for 7.8% of global chemical fertilizer use, underscoring a yield–chemical tradeoff. Although Farmer Field Schools (FFS) are known to raise yields or curb chemical inputs, the literature has overlooked two dimensions—production input substitution and system-wide production efficiency. Using 257 farm-level observations from vegetable farms in Beijing, this study contributes by conducting a production efficiency analysis of inputs (labor, irrigation water, fertilizers, pesticides) and outputs (tomato yield, net income) to estimate the direct and spillover effects of FFS on productivity, efficiency, and environmental performance. The results showed that FFS participation is associated with lower labor use and reduced fertilizer and pesticide intensities, while increasing yield, net income, and production efficiency. Smaller but similar improvements were observed among non-participating neighbors, indicating the existence of spillover effects. These findings highlight FFS as a scalable approach for jointly improving the economic welfare and environmental practices of farms in China’s vegetable sector.